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- Analyses of the fatigue crack propagation
process and stress ratio effects using the two parameter method
J. Zhang, X. D. He and S. Y. Du.
International Journal of Fatigue, Vol. 27, No. 10-12, Oct.-Dec.
2005, pp. 1314-1318.
In situ SEM observations have revealed that fatigue crack
propagation in aluminium alloys is caused by the shear band
decohesion around the crack tip. The formation and cracking
of the shear band is mainly caused by the plasticity generated
in the loading part of a load cycle. This shear band decohesion
process has been observed to occur in a continuous way over
the time period during the loading part of a cycle. Based
on this observation, in this study, a new parameter has been
introduced to describe fatigue crack propagation rate. This
new parameter, daldS, defines the fatigue crack propagation
rate with the change of the applied stress at any moment of
a stress cycle. The relationship between this new parameter
and the conventional daldN parameter which describes fatigue
crack propagation rate per stress cycle is given. Using this
new parameter, it is proven that two loading parameters are
necessary in order to accurately describe fatigue crack propagation
rate per stress cycle, da/dN. An analysis is performed and
a general fatigue crack propagation model is developed. This
model has the ability to describe the four general type of
fatigue crack propagation behaviours summarised by Vasudevan
and Sadananda.
- Development of a Fiber-Optic Accelerometer
for Third-Party Damage Detection
Jae Young Nam, Jae Boong Choi, Young Jin Kim and Chang Ryul
Pyo.
Key Engineering Materials, Vol. 297-300, Part 3, 2005, pp.
1979-1984. Nov.
The objective of this paper is to develop a fiber optic accelerometer
applicable to third party damage detection system. A fiber
optic accelerometer was developed by use of combining principles
of one degree of freedom vibration model and an extrinsic
Fabry-Perot interferometer. The developed fiber optic accelerometer
was designed to perform with a sensitivity of 0.06mV/g, a
frequency range of less than 6kHz and an amplitude range of
-200g to 200g. The developed accelerometer was compared with
a piezoelectric accelerometer and calibrated. In order to
verify the developed accelerometer, the field experiment was
performed. From the field experiment, vibration signals and
the location of impact were successfully detected. The developed
accelerometer is expected to be used for the third party damage
detection system which requires long distance transmission
of signals. (Application: inspection of underground natural
gas pipelines.)
- Development of Fe-Mn-Si-Cr Shape Memory
Alloy Fiber Reinforced Plaster-based Smart Composites
Teppei Wakatsuki, Yoshimi Watanabe and Hiroshi Okada.
Materials Science Forum, Vol. 475-479, Part 3, 2005, pp.
2063-2066.
In previous studies, it has been found that the shape memory
effect of the embedded straight and wavy shape memory alloy
(SMA) fibers enhance the strength and energy absorption prior
to fracture of the composite, where the embedded SMA fibers
shrink due to their shape memory effect. In the case of wavy
fiber reinforced composites, the SMA fibers were subjected
to pre-tensile strain using fiber holder with rotatable rollers
to maintain the constant periodicity and amplitude of wavy
fibers. In this study, on the other hand, the wavy SMA fibers
were subjected to pre-tensile strain without using fiber holder,
and therefore, periodicity and amplitude of wavy fibers were
varied during the deformation. Then the wavy SMA fiber reinforced
smart composite is fabricated. For the mechanical property
characterization, three-point bending test is performed for
the specimens.
- Effect of aging treatment on high temperature
strength of Nb added ferritic stainless steels
Jae Cheon Ahn, Gyu Man Sim and Kyung Sub Lee.
Materials Science Forum, Vol. 475-479, Part 1, 2005, pp.
191-194.
Effects of aging treatment on high temperature strength of
Nb added ferritic stainless steels for automotive parts were
investigated. Hot tensile tests were carried out at 700 deg
C after the aging at 700 deg C for different aging times using
Gleeble 1500. High temperature strength of all steels decreased
as the aging time increased. In Nb free steels, the reduction
in high temperature strength is mainly due to grain growth.
On the other hand, in Nb added steels, the reduction in high
temperature strength occurred by Nb precipitation. It was
observed that Fe2Nb (Laves phase), Nb(C,N) and Fe3Nb3C were
precipitated out during the aging at 700 C in Nb added steels.
The coarsening rate of Fe2Nb was higher than that of Nb(C,N).
Fine Fe2Nb precipitates formed during at the early stage of
aging contributed to high temperature strength in 0.01C-0.38Nb
steel. However, coarse Fe2Nb particles formed during the aging
were very detrimental to high temperature strength. The coarsening
of Fe2Nb was relatively retarded by adding Mo.
- Effects of laser irradiation on iron
loss reduction for Fe-3%Si grain-oriented silicon steel
Muneyuki Imafuku, Hiroshi Suzuki, Koichi Akita, Keiji Iwata
and Masahiro Fujikura.
Acta Materialia, Vol. 53, No. 4, Feb. 2005, pp. 939-945.
The effects of laser irradiation on iron loss reduction for
Fe-3%Si grain-oriented silicon steel sheet were investigated.
The local tensile residual stress states near the laser irradiated
cavity lines were observed by using the new X-ray stress measurement
method for a single crystal. Although the higher laser power
induced the larger tensile residual stresses, the minimum
iron loss was obtained at the medium tensile residual stress
conditions of about 100-200 MPa. The increase of Vickers hardness
was observed with increasing laser power, which was the mark
of the plastic deformations induced by the laser irradiation.
The tensile residual stress reduces eddy current loss and
the plastic deformation increases hysteresis loss of the material.
The total iron loss is determined by the balance of these
two effects of laser irradiation.
- Electrochemical oxidation of Mn/MnO
films: formation of an electrochemical capacitor
B. Djurfors, J. N. Broughton, M. J. Brett and D. G. Ivey.
Acta Materialia, Vol. 53, No. 4, Feb. 2005, pp. 957-965.
An in-depth study of the oxidation step required to produce
electrochemical capacitors from porous manganese-oxide materials
was carried out. The oxidation process takes place under the
application of a small anodic current in a solution of 1 M
Na2SO4, resulting in the formation of a three-layered structure.
During the oxidation process, a base layer of undisturbed
zigzag material oxidizes from Mn/MnO to Mn3O4. At the same
time, a second layer forms directly on the surface of the
zigzag material. The layer is partly crystalline Mn3O4 and
partly amorphous. The final and most important layer is the
amorphous, hydrated MnO2 surface film. It is believed that
this layer is solely responsible for the capacitive behavior
of these films. The porosity of the electrode prior to oxidation
is shown to be immaterial as oxidation of a fully dense film
results in similarly high capacitive values attributed to
the formation of a porous surface layer.
- End user searching: a Web log analysis
of NAVER, a Korean Web search engine
Soyeon Park, Joon Ho Lee and Hee Jin Bae.
Library and Information Science Research, Vol. 27, No. 2,
2005, pp. 203-221.
Transaction logs of NAVER, a major Korean Web search engine,
were analyzed to track the information-seeking behavior of
Korean Web users. These transaction logs include more than
40 million queries collected over 1 week. This study examines
current transaction log analysis methodologies and proposes
a method for log cleaning, session definition, and query classification.
A term definition method which is necessary for Korean transaction
log analysis is also discussed. The results of this study
show that users behave in a simple way: they type in short
queries with a few query terms, seldom use advanced features,
and view few results' pages. Users also behave in a passive
way: they seldom change search environments set by the system.
It is of interest that users tend to change their queries
totally rather than adding or deleting terms to modify the
previous queries. The results of this study might contribute
to the development of more efficient and effective Web search
engines and services. (Original abstract)
- From the search problem through query
formulation to results on the web
Judit Bar-Ilan and Elena Barsky.
Online Information Review, Vol. 29, No. 1, 2005, pp. 75-89.
Purpose: The purpose of the research was to create internet
search instructions, to test their effectiveness and to track
the search behavior of first year MLS students. Design/methodology/approach:
The students received two exercises with similar search tasks.
No specific search guidelines were delivered to the students
prior to the first exercise. Prior to the second exercise
students received a lecture based on the internet search instructions
developed by the authors. The results of the two searches
were analyzed and compared. Findings: As a result of the lecture
students significantly improved the search results. There
were a certain number of problematic search behavior patterns
and obstacles uncovered, which proved to have a critical impact
on the search results, such as: difficulties in acquiring
new or alternative vocabulary during the search process, perception
of the task as the ultimate source of keywords, and perception
of commercial sources as unavailable. Research limitations/implications:
In order to understand the effect of the internet search instructions,
the experiment has to be repeated with other groups of users.
If the results consistently show that search behavior improves,
the authors recommend systematic training of internet users.
Originality/value: The paper might be particularly interesting
for information specialists and search instructors mostly
because it reveals connection between the way the problem
was stated and initial search strategy - a connection that
to our knowledge has not been deeply explored yet. (Original
abstract - amended)
- Google Scholar: the pros and the cons
Péter Jacsó.
Online Information Review, Vol. 29, No. 2, 2005, pp. 208-214.
Purpose: To identify the pros and the cons of Google Scholar.
Design/methodology/approach: Chronicles the recent history
of the Google Scholar search engine from its inception in
November 2004 and critiques it with regard to its merits and
demerits. Findings: Feels that there are massive content omissions
presently but that, with future changes in its structure,
Google Scholar will become an excellent free tool for scholarly
information discovery and retrieval. Originality/value: Presents
a useful analysis for potential users of the Google Scholar
site. (Original abstract)
- How experts and novices search the
Web
Diana Tabatabai and Bruce M. Shore.
Library and Information Science Research, Vol. 27, No. 2,
2005, pp. 222-248.
Searching for information pervades a wide spectrum of human
activity, including learning and problem solving. With recent
changes in the amount of information available and the variety
of means of retrieval, there is even more need to understand
why some searchers are more successful than others. This study
was undertaken to advance the understanding of expertise in
seeking information on the Web by identifying strategies and
attributes that will increase the chance of a successful search
on the Web. The strategies were as follows: evaluation, navigation,
affect, metacognition, cognition, and prior knowledge, and
attributes included age, sex, years of experience, computer
knowledge, and info-seeking knowledge. Success was defined
as finding a target topic within 30 minutes. Participants
were from three groups. Novices were 10 undergraduate pre-service
teachers, intermediates were 9 final-year master of library
and information studies students, and experts were 10 highly
experienced professional librarians working in a variety of
settings. Participants' verbal protocols were transcribed
verbatim into a text file and coded. These codes, along with
Internet temporary files, a background questionnaire, and
a post-task interview were the sources of the data. Since
the variable of interest was the time to finding the topic,
in addition to ANOVA and Pearson correlation, survival analysis
was used to explore the data. The most significant differences
in patterns of search between novices and experts were found
in the cognitive, metacognitive, and prior knowledge strategies.
Survival analysis revealed specific actions associated with
success in Web searching: (1) using clear criteria to evaluate
sites, (2) not excessively navigating, (3) reflecting on strategies
and monitoring progress, (4) having background knowledge about
information seeking, and (5) approaching the search with a
positive attitude. (Original abstract)
- In situ neutron diffraction of heavily
drawn steel wires with ultra-high strength under tensile loading
Y. Tomota, T. Suzuki and A. Kanie, et al.
Acta Materialia, Vol. 53, No. 2, Jan. 2005, pp. 463-467.
To make clear the strengthening mechanism of heavily drawn
steel wires exhibiting ultra-high strength, in situ neutron
diffraction during tensile loading was performed. A ferrite
steel (FK) subjected to a true strain of 6.6 and a pearlite
steel (PS) subjected to 4.0 were extended on a tensile tester
and (1 10) diffraction profiles were measured at various holding
stresses. Tensile strengths of steel FK and PS are 1.7 and
3.7 GPa, respectively. The change in (1 10) spacing with tensile
stress is reversible, i.e., elastic, close to the relevant
tensile strength. A stress versus (1 10) lattice plane strain
is linear for steel FK while evidently nonlinear at higher
stresses for steel PS. In steel PS in which cementite peaks
were hardly observed, the strengthening mechanism is postulated
to be different from that for as-patented pearlite steels.
- INTERFACE STRUCTURES AND DIFFUSION
PATHS IN SiC/METAL COUPLES
Masaaki Naka, Takashi Fukai and Julius C. Schuster.
Inc , 735 Ceramic Place, Westerville, OH, 43081, USA, [URL:http://www.ceramics.org]:
American Ceramic Society, 2005,
The interface structures between SiC and metal are reviewed
in SiC/metal systems. Metals are divided into two groups,
carbide forming metals and non-carbide forming metals. Carbide
forming metals form metal carbide on the metal side, and metal
silicide on the SiC side. Further diffusion of Si and C from
SiC causes the formation of a ternary phase. Non-carbide forming
metals form a metal silicide containing graphite or a layered
structure consisting of metal silicide and metal silicide
containing graphite. The diffusion path between SiC and metal
are formed along tie-lines connecting SiC and metal on the
corresponding ternary Si-C-M phase diagram. The reactivity
of metals is dominated by the formation of carbide or silicide.
The reactivities of elements are discussed relative to their
positions in the periodical table of elements, and Ti shows
the highest reactivity among carbide forming metals. For non-carbide
forming metals the reactivity sequence is Fe > Ni > Co. Detailed
knowledge of phase reactions and diffusion paths for SiC/metal
systems are needed in order to control the interface structures
in SiC/metal joints at high temperatures. (Also considered:
Ti, Zr, Hf, V, Nb, Ta, Cr, Mo, W.)
- Microstructure and precipitation in
Al-Li-Cu-Mg-(Mn, Zr) alloys
N. Gao, M. J. Starink, L. Davin, A. Cerezo, S. C. Wang and
P. J. Gregson.
Materials Science and Technology, Vol. 21, No. 9, Sept. 2005,
pp. 1010-1018.
Hot rolled Al-6Li-1Cu-1Mg-0.2Mn (at.-%) (Al-1.6Li-2.2Cu-0.9Mg-0.4Mn,
wt-%) and Al-6Li-1 Cu-1 Mg-0.03Zr (at.-%) (Al-1.6Li-2.3Cu-1
Mg-0.1Zr, wt-%) alloys developed for age forming were studied
by tensile testing, electron backscatter diffraction (EBSD),
three-dimensional atom probe (3DAP), transmission electron
microscopy (TEM) and differential scanning calorimetry (DSC).
For both alloys, DSC analysis shows that ageing at 150DGC
leads initially to formation of zones/clusters, which are
later gradually replaced by S phase. On ageing at 190DGC,
S phase formation is completed within 12 h. The precipitates
identified by 3DAP and TEM can be classified into (a) Li rich
clusters containing Cu and Mg, (b) a plate shaped metastable
precipitate (similar to GPB2 zones/S"), (c) S phase and (d)
delta spherical particles rich in Li. The Zr containing alloy
also contains beta' (Al3Zr) precipitates and composite beta'/delta'
particles. The beta' precipitates reduce recrystallisation
and grain growth leading to fine grains and subgrains. Age
forming is a key innovation in the fabrication of curved structural
components for aerospace applications, e.g. wing skin.
- Nondestructive testing of the space
shuttle external tank foam insulation using near field and focused
millimeter wave techniques
S. Kharkovsky, F. Hepburn, J. Walker and R. Zoughi.
Materials Evaluation, Vol. 63, No. 5, May 2005, pp. 516-522.
The space shuttle Columbia's catastrophic failure has been
attributed to a piece of external tank spray on foam insulation
striking the left wing of the orbiter, causing significant
damage to some of the reinforced carbon/carbon leading edge
wing panels. Subsequently, several nondestructive testing
(NDT) techniques have been considered for testing the external
tank. One such technique involves using millimeter waves,
which have been shown to easily penetrate the foam and provide
high resolution images of its interior structures. This paper
presents the results of testing three different spray on foam
insulation covered panels by reflectometers at millimeter
wave frequencies, specifically at 100 GHz. Each panel was
fitted with various embedded discontinuities/inserts representing
voids and unbonds of different shapes, sizes and locations
within each panel. In conjunction with these reflectometers,
radiators, including a focused lens antenna and a small horn
antenna, were used. The focused lens antenna provided for
a footprint diameter of approximately 12.5 mm (0.5 in.) at
254 mm (10 in.) away from the lens surface. The horn antenna
was primarily operated in its near field for obtaining relatively
high resolution images. These images were produced using two
dimensional scanning mechanisms. Discussion of the difference
between the capabilities of these two types of antennas (radiators)
for the purpose of testing the spray on foam insulation as
it relates to the produced images is also presented. Keywords:
millimeter waves, near field, insulating foam, spray on foam
insulation, unbond, void, focusing lens, horn antenna.
- Visualizing overlap and rank differences
among web-wide search engines: Some free tools and services
Peter Jacso.
Online Information Review, Vol. 29, No. 5, 2005, pp. 554-560.
Purpose: To compare the performance of different search engines,
highlighting the overlap and rank differences. Design/methodology/approach:
Presents results of an overlap test search series among traditional
CD-ROM indexing/abstracting databases since the mid-1980s,
web databases, and authors' own polysearch engine, and reviews
Google Scholar. Findings: Finds that overlap is minimal among
web-wide search engines which crawl and index the mostly unstructured
open web; and that overlap among Google Scholar and the native
search engines is far less than the ideal 100 per cent in
the optimal context of crawling and indexing highly-structured
and metadata-rich collections. Originality/value: Reinforces
the existing view that for comprehensive searches one must
search more than one database. Highlights and recommends several
very good search engine sites. (Original abstract)
- The web as a free source for scientific
information: a comparison with fee-based databases
Luisa M. Doldi and Erwin Bratengeyer.
Online Information Review, Vol. 29, No. 4, 2005, pp. 400-411.
Purpose: The aim of this study was an evaluation of the web
as a source of scientific bibliographic information. Design/methodology/approach:
In order to give this evaluation a quantitative dimension,
a comparison with the information obtained from fee-based
bibliographic databases was performed. Based on a concrete
search example in the field of plant production biotechnology,
a comparative study of selected fee-based bibliographic databases
(CAB Abstracts and Biosis Preview) and a search of the web
with selected search engines (Scirus and Google) was carried
out. A comparison of the information retrieved through the
databases and that retrieved through search engines was conducted
with respect to the quantity and quality of retrieved documents,
search time, the cost of information, retrieval strategies,
the reliability of information and the demands on the skills
of the searcher. Findings: The surprising results of this
comparison clearly indicate that the web, assuming a professional
use of the medium, is not only a valuable source for scientific
information, but also provides the scientific community with
an instrument to make knowledge available and accessible for
almost anyone. Originality/value: This study shows that the
web has reached a certain level of maturity in regard to scientific
and qualitative content and can be considered a worthwhile
source of scientific information. (Original abstract)
- Web search strategies and human individual
differences: a combined analysis
Nigel Ford, David Miller and Nicola Moss.
Journal of the American Society for Information Science and
Technology, Vol. 56, No. 7, May 2005, pp. 757-764.
This is the second of two articles published in this issue
of JASIST reporting the results of a study investigating relationships
between Web search strategies and a range of human individual
differences. In this article we provide a combined analysis
of the factor analyses previously presented separately in
relation to each of three groups of human individual difference
(study approaches, cognitive and demographic features, and
perceptions of and approaches to Internet-based information
seeking). It also introduces two series of regression analyses
conducted on data spanning all three individual difference
groups. The results are discussed in terms of the extent to
which they satisfy the original aim of this exploratory research,
namely to identify any relationships between search strategy
and individual difference variables for which there is a prima
facie case for more focused systematic study. It is argued
that a number of such relationships do exist. The results
of the project are summarized and suggestions are made for
further research. (Original abstract)
- Web search strategies and human individual
differences: cognitive and demographic factors, internet attitudes,
and approaches
Nigel Ford, David Miller and Nicola Moss.
Journal of the American Society for Information Science and
Technology, Vol. 56, No. 7, May 2005, pp. 741-756.
The research reported here was an exploratory study that
sought to discover the effects of human individual differences
on Web search strategy. These differences consisted of (a)
study approaches, (b) cognitive and demographic features,
and (c) perceptions of and preferred approaches to Web-based
information seeking. Sixty-eight master's students used AltaVista
to search for information on three assigned search topics
graded in terms of complexity. Five hundred seven search queries
were factor analyzed to identify relationships between the
individual difference variables and Boolean and best-match
search strategies. A number of consistent patterns of relationship
were found. As task complexity increased, a number of strategic
shifts were also observed on the part of searchers possessing
particular combinations of characteristics. A second article
(published in this issue of JASIST; Ford, Miller, & Moss,
2005) presents a combined analyses of the data including a
series of regression analyses. (Original abstract)
- Citation-enhanced indexing/abstracting
databases
Peter Jacso.
Online Information Review, Vol. 28, No. 3, 2004, pp. 235-238.
Provides an introductory look at what savvy users should
know about the implications of having information about cited
references in I /A records. Looks at the more sophisticated,
link-enabled cited references and the novel citation scores
in full-text collections, then discusses the alternatives
for searching efficiently by elements of cited references:
cited author, cited title, cited source and cited year in
I/A databases and full-text archives. (Original abstract)
- Date-restricted queries in web search
engines
Dirk Lewandowski.
Online Information Review, Vol. 28, No. 6, 2004, pp. 420-427.
Search engines usually offer a date-restricted search on
their advanced search pages. But determining the actual update
of a web page is not without problems. Conducts a study testing
date-restricted queries on the search engines Google, Teoma
and Yahoo! Finds that these searches fail to work properly
in the engines examined. Finally, discusses implications of
this for further research and search engine development. (Original
abstract)
- Index use by engineering faculty and
students
Bette Finn and Pat Johnston.
Georgia Library Quarterly, Vol. 41, No. 3, Fall 2004, pp.
5-15.
Reports the results of a user study, undertaken at Georgia
Institute of Technology (Georgia Tech), to determine the information
seeking behaviour of faculty and graduate students, with particular
reference to the Civil and Environmental Engineering schools,
their use of abstracting and indexing services (AandIs) and
primary information sources. Analyzes the resulting data to
determine whether faculty and graduate research is in compliance
with Association for College and Research Libraries (ACRL)
Information Literacy Standards for index use. Concludes that,
although a majority of the researchers do use AandIs, there
is concern about those who do not use them. A further concern
is the current trend for researchers to go directly to the
full text databases, such as IEEE Xplore, Science Direct and
Google-type searching on the World Wide Web, with some searchers
eliminating the vital index searching process. (Original abstract
- amended)
- Online IR system evaluation: online
databases versus Web search engines
Hong Xie.
Online Information Review, Vol. 28, No. 3, 2004, pp. 211-219.
This study evaluated two different types of online information
retrieval (IR) systems: online databases and Web search engines,
in terms of user generated criteria. It also compares four
types of Web search engines: directories, search engines,
meta-search engines, and specialized search engines. The results
show that three elements are essential to users in the evaluation
of online IR systems: interface design, system performance
and collection coverage. While participants preferred the
ease of use and intuitive interfaces of Web search engines,
they also liked the credible and useful information offered
by online databases. Based on the discussion of advantages
and problems of online databases and Web search engines, implications
of for the design of IR systems are further suggested. (Original
abstract)
- Out of my searcher's mind, or whatever
happened to Kay Francis?
Barbara Quint.
Online, Vol. 28, No. 6, Nov 2004-Dec 2004, pp. 35-38.
Presents a follow-up to an earlier two-part article, written
by the author (Online, 15 (3) May 1991. pp.13-18; 15 (4) July
1991, pp.28-35), in which she identified seven stages to be
undertaken by the users when planning and executing an online
search. The aim is to compare the pre-Internet conditions
of 1991 for online searching with those applying to the present.
Two of the original factors have disappeared from the equation:
the fact that online searching was undertaken by professional
searchers and not end-users; and the high cost of searching
which made faster searching and less relevant documents retrieved
the keys to cheap searches. The mass Internet search engines,
such as Google and Yahoo! have eliminated these two factors
almost completely. Uses the example of an online search for
the film star, Kay Francis, to reveal what is better and what
is worse about the current online searching environment compared
with the past.
- Reformulation of consumer health queries
with professional terminology: a pilot study
Robert M. Plovnick and Qing T. Zeng.
Journal of Medical Internet Research, Vol. 6, No. 3, Jul
2004-Sep 2004, pp. .
The full text of this electronic journal article can be found
at [URL:http://www.jmir.org/2004/3/e27/]. Background: The
Internet is becoming an increasingly important resource for
health-information seekers. However, consumers often do not
use effective search strategies. Query reformulation is one
potential intervention to improve the effectiveness of consumer
searches. Objective: The project endeavoured to answer the
research question: "Does reformulating original consumer queries
with preferred terminology from the Unified Medical Language
System (UMLS) Metathesaurus lead to better search returns?"
Methods: Consumer-generated queries with known goals (n=16)
that could be mapped to UMLS Metathesaurus terminology were
used as test samples. Reformulated queries were generated
by replacing user terms with Metathesaurus-preferred synonyms
(n=18). Searches (n=36) were performed using both a consumer
information site and a general search engine. Top 30 precision
was used as a performance indicator to compare the performance
of the original and reformulated queries. Results: Forty-two
percent of the searches utilizing reformulated queries yielded
better search returns than their associated original queries,
19% yielded worse results, and the results for the remaining
39% did not change. We identified ambiguous lay terms, expansion
of acronyms, and arcane professional terms as causes for changes
in performance. Conclusions: We noted a trend towards increased
precision when providing substitutions for lay terms, abbreviations,
and acronyms. We have found qualitative evidence that reformulating
queries with professional terminology may be a promising strategy
to improve consumer health-information searches, although
we caution that automated reformulation could in fact worsen
search performance when the terminology is ill-fitted or arcane.
(Original abstract)
- Retrieval features for online databases:
common, unique, and expected
Nor Sahlawaty Halim and Roslina Othman.
Online Information Review, Vol. 28, No. 3, 2004, pp. 200-210.
The aims of this study were to identify the retrieval features
for online databases; difficulties faced by users; and retrieval
features expected by users. A total of 25 databases were surveyed
and 40 users were interviewed after the training sessions.
Common retrieval features included Boolean operators, phrase
searching, match of exact words or phrases, field specific
and limit fields searches, truncation, and wildcard. Even
though features are offered in many systems, their interpretation
and implementation are different. Unique features included
lateral searching, density and frequency of terms, reference
link, and searching via table of content. The expected features
included relevance feedback and term weighting other than
those already offered by ACM Digital Library and IEEE Xplore.
Such expectations were influenced by the users' background
in ICT. Difficulties included application of the retrieval
features in searching. Database providers must include the
expected features, synonyms linked to terms in the thesaurus,
and extensive search examples. (Original abstract)
- Web users' information retrieval methods
and skills
Carol S. Bond.
Online Information Review, Vol. 28, No. 4, 2004, pp. 254-259.
When trying to locate information on the Web people are faced
with a variety of options. This research reviewed how a group
of health related professionals approached the task of finding
a named document. Most were eventually successful, but the
majority encountered problems in their search techniques.
Even experienced Web users had problems when working with
a different interface to normal, and without access to their
favourites. No relationship was found between the number of
years' experience Web users had and the efficiency of their
searching strategy. The research concludes that if people
are to be able to use the Web quickly and efficiently as an
effective information retrieval tool, as opposed to a recreational
tool to surf the Internet, they need to have both an understanding
of the medium and the tools, and the skills to use them effectively,
both of which were lacking in the majority of participants
in this study. (Original abstract)
- A growing player: IDS Version 6.0 from
CSA
M. L. Fulton.
Searcher, Vol. 11, No. 5, May 2003, pp. 57-61.
Reviews the facilities provided for online searchers by the
Internet Database Service (IDS) Version 6.0, produced by CSA
(formerly Cambridge Scientific Abstracts). IDS provides World
Wide Web access to over 70 databases covering major areas
of science and social science research. Concludes that IDS
allows searchers: to search multiple databases quickly (even
if dial-up connections are still in use); to determine if
the library has electronic access to specific resources and
link directly to the full text of resources available in the
library collection; to build a database using the user's own
bibliographic/database manager or the one offered by CSA;
to send a list of references via electronic mail to the user's
home email address or to another party; to save up to 20 search
strategies for a period of 6 months; and to save a search
alert to search automatically selected databases for new content
every week. Concludes that the resource has quality content
with quality indexing and abstracting and the tools and linking
capabilities help the content work well. (Quotes from original
text)
- Internet librarian
Julia Gelfand, Kris Kasianovitz and Colby Riggs.
Library Hi Tech News, Vol. 20, No. 1, Jan 2003-Feb 2003,
pp. 13-16.
The 2002 Internet Librarian Conference "Navigating in turbulent
waters" was held 4-6 November, 2002, in Palm Springs, California.
The conference was a mixture of leading-edge ideas, tools,
expert speakers, and events focused on information professionals
and Internet-related technologies. It featured 4 keynote sessions,
over 100 speakers in 4 simultaneous tracks each day for a
total of 12 different themes: virtual services; knowledge
sharing applications; E-learning and training; Wireless Web
world; search engines; future focus; E-resources; Web operations
and opportunities; searchers and search strategies, Intranets
and portals, DRM tools and technologies, and Web design and
development. For more information see http: //www.infotoday.com/il2002/default.htm.
- Searching the online catalog and the
World Wide Web
Shu-Hsien L. Chen.
Journal of Educational Media and Library Sciences, Vol. 41,
No. 1, Sep 2003, pp. 29-43.
The article discusses the searching behaviors of school children
using the online catalog and the World Wide Web. The amount
of information and search capability for the online catalog
and the World Wide Web, though, differ to a great extent,
students share several common problems in using them. They
have problems in spelling and typing, phrasing of search terms,
extracting key concept, formulating search strategy, and evaluating
search results. Their specific problems of searching the World
Wide Web include rapid navigation of the Internet, overuse
of "Back" button and browsing strategy, and evaluating only
the first screen. Teachers and media specialists need to address
these problems in the instruction of information literacy
skills so that students can fully utilize the power of online
searching and become efficient information searchers. (Original
abstract)
- Hoe zoeken de nieuwe zoeksystemen.
How the new search systems work
E. Sieverts.
Informatie Professional, Vol. 6, No. 4, Apr 2002, p.26-9
2002, pp. .
The wealth of information available via the worldwide web
together with the wide range of subjects covered and lack
of any organised structure place heavy demands on retrieval
systems. Moreover, intranet users require greater precision
from search results than internet users. Google determines
relevancy by examining the number of links to each document.
The frequency with which search terms appear in the text or
title of a document is also important. Some systems offer
users the opportunity to refine search strategies at each
stage.
- Web search strategies and retrieval
effectiveness: an empirical study
N. Ford, D. Miller and N. Moss.
Journal of Documentation, Vol. 58, No. 1, 2002, pp. 30-48.
Reports the results of a study that investigated links between
Web search strategies and retrieval effectiveness. 68 masters
students of librarianship, information management and information
systems searched for two topics using the AltaVista search
engine. Logs of the resultant 341 queries, along with relevance
judgements for over 4,000 retrieved items, were analyzed using
factor analysis and regression. Presents and discusses the
differing but complementary types and strengths of evidence
produced by these two forms of analysis. Retrieval effectiveness
was associated positively with best match searching and negatively
with Boolean searching. Discusses the implications of these
findings for Web searching. (Original abstract - amended)
- Exploring users' experiences of the
Web
B. Brown and A. Sellen.
First Monday, Vol. 6, No. 9, Sep 2001.
The full text of this electronic journal article can be found
at [URL:http://www.firstmonday.dk/issues/issue6_9/brown/].
While browsing the Web is a widespread everyday activity there
is a shortage of detailed understanding of how users organize
their Web usage. Reports results from a qualitative in-depth
interview study of how users browse the Web and combine browsing
with their other activities. The data are used to explore
three particular problems which users have with browsing the
Web. Firstly, users have problems managing their favourites,
and in particular accessing their favourites through a hierarchical
menu. Second, users have problems with combining information
across different Web sites (the 'meta-task' problem). Third,
users have concerns with security and privacy, although these
concerns seem to change as users become more experienced with
shopping on the Web. Discusses three concepts which address
these problems: home page favourites; Web clipping; and the
Web card. These concepts are attempts at incremental improvements
to the Web without affecting the Web's essential simplicity.
(Original abstract)
- Mouse click plagiarism: the role of
technology in plagiarism and the librarian's role in combating
it
N. J. Auer and E. M. Krupar.
Library Trends, Vol. 49, No. 3, Winter 2001, pp. 415-432.
Article included in a special issue devoted to the theme:
Ethical issues in information technology. The proliferation
of full text databases and the World Wide Web has made plagiarism
a rapidly growing problem in academia. Possible factors influencing
student behaviour and attitudes toward plagiarism include
ignorance, lack of personal investment in their education,
situational ethics and lack of consistent styles among and
within various disciplines. Librarians are in a unique position
to help prevent and detect plagiarism by forming partnerships
with faculty to re-examine assignments and instructional sessions
and by informing them of Internet paper mills and useful Internet
search strategies. (Original abstract)
- The role of individual differences
in Internet searching: an empirical study
N. Ford, D. Miller and N. Moss.
Journal of the American Society for Information Science and
Technology, Vol. 52, No. 12, Oct 2001, pp. 1049-1066.
Reports the results of a study of the role of individual
differences in Internet searching. The dimensions of individual
differences forming the focus of the research consisted of:
cognitive styles; levels of prior experience; Internet perceptions;
study approaches; age; and gender. 69 Masters students searched
for information on a prescribed topic using the AltaVista
search engine. Results were assessed using simple binary relevance
judgements. Factor analysis and multiple regression revealed
interesting differences, retrieval effectiveness being linked
to: male gender; low cognitive complexity; an imager (as opposed
to verbalizer) cognitive style; and a number of Internet perceptions
and study approaches grouped here as indicating low self efficacy.
Discusses the implications of these findings for system development
and for future research. (Original abstract - amended)
- A study of the use of electronic information
systems by higher education students in the UK
C. Armstrong, R. Fenton, R. Lonsdale, D. Stoker, R. Thomas
and C. Urquhart.
Program, Vol. 35, No. 3, Jul 2001, pp. 241-262.
Reports findings from the first annual cycle of a three-year
research project on the provision and use of electronic information
systems (EIS) within higher education in the UK. The project,
JISC User Surveys: Trends in Electronic Information Services
(JUSTEIS), was funded by the Joint Information Systems Committee
(JISC) and undertaken at the University of Wales, Aberystwyth
(UWA). Students, academics and library staff in 25 universities
were surveyed using critical incident and critical success
factors methodologies to ascertain the range and nature of
EIS use. Provision of these systems by higher education institutions
was also investigated via an analysis of their library Web
sites. The findings reported in this paper focus on student
use and the purposes for which EIS are employed, and reveal
the limited array of EIS used and the ad hoc nature of search
strategies adopted across undergraduate and postgraduate bodies
within a range of disciplines. There appears to be little
or no variation in the pattern of EIS use by the various student
groups studied: the effect of the Internet on information
seeking by students is hugely significant and the more formal
resources, such as JISC-negotiated resources are little used.
There is little evidence of coherent search strategies used
by students. Recommendations for both the JISC and higher
education are offered. (One author may be contacted by electronic
mail at [mailto:rff@aber.ac.uk]). (Original abstract)
- Users' perceptions of the Web as revealed
by transaction log analysis
H. Moukdad and A. Large.
Online Information Review, Vol. 25, No. 6, 2001, pp. 349-358.
When information seekers use an information retrieval system
their strategy is based, at least in part, on the perceptions
they have formed about that environment. A random sample was
gathered of more than 2,000 actual search queries submitted
by users (at an unspecified university library) to one World
Wide Web search engine, WebCrawler, in two separate capture
sessions. The results suggest that a high proportion of users
do not employ advanced search features and those who do frequently
misunderstand them. Furthermore, many users seem to have formed
a model of the Web that imbues it with the intelligence found
in a reference librarian, for example, but not a retrieval
system. The linguistic structure of many queries resembles
a typical human-human communication model that is unlikely
to produce satisfactory results in a human-computer communication
environment, such as that offered currently by the Web. Design
of more intuitive systems is dependent upon a more complete
understanding of user behaviour at the intellectual and emotional
as well as the technical levels. (Original abstract)
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